How to prepare a file for an online application
A practical AttachReady workflow: check upload requirements, choose an image or PDF tool, inspect the result, and download a file you can submit.
An upload-ready file needs to satisfy the receiving website's rules, not just open on your computer. Before changing anything, copy the accepted formats, maximum file size, pixel dimensions or page limit from that website. Keep the original and work on a copy.
Start with the requirement that is failing
| Upload requirement | First tool to try | What to verify afterward |
|---|---|---|
| A photo below 200 KB | Image compressor | Actual bytes and legible detail |
| Exact pixel dimensions | Resize images or Crop images | Width, height and aspect ratio |
| One PDF made from photos | Images to PDF | Page order, orientation and total bytes |
| A smaller existing PDF | PDF compressor | Text readability and page count |
| Several documents in one file | Merge PDFs | Correct order and no missing pages |
For example, a portal may require JPEG, no more than 200,000 bytes, and 600 × 800 pixels. Converting PNG to JPEG fixes the format; resizing fixes dimensions; compression fixes the byte limit. None of those steps alone proves that every requirement is met.
Choose a processing mode deliberately
The explicitly local inspection and image-compression controls work inside your browser. Other operations send the selected file to the processing service. Guests can use supported basic server tools without an account, within the limits shown on the page. Account tools add reusable file references, rules, history and API/MCP access. Check formats and limits before uploading a large batch.
Strict mode only accepts an output when the requested rules pass. Best-effort mode may return a usable candidate that misses a target: read its warning instead of treating a download button as proof of compliance.
Check the downloaded result
Open the output, zoom in on small text and faces, and compare its actual size with the portal's limit. Review page order and orientation. Keep the filename simple and retain the real output extension. Renaming scan.png to scan.pdf does not convert its bytes.
Guest outputs remain in the current page, so download before navigating away. Account tool uploads and artifacts have time-limited access; save anything you need to keep. File privacy and retention explains the difference.
If the upload still fails, follow the upload troubleshooting checklist. AttachReady checks technical file requirements; the receiving organization makes the final decision about your submission.